Coursera.org has been a part of Highbrows' skill development drive. The site facilitates the world's top universities to offer free online courses to international students. Although the antecedent post is about an entrepreneurship course, Coursera offers much of the courses relevant to applied sciences. Spreading awareness about such platforms to undergraduates and school students might help them improvise their aspiration or learn on top of their current skills in applied sciences and many related fields.

Friday, November 22, 2013

A Russian photographer, Alexey Kljatov created a self made camera-lens combination to take some inexpensive photographs of snowflakes that clearly show the crystallographic structure of each flake.

With each flake having undergone different thermodynamics, no two flakes are alike. What is interesting is that each flake shows the basic most thermodynamic concepts with respect to crystallography at a macro level.

The dendrites grow spaced from each other like leafs on a branch instead of a single solid being frozen because, at the seed's surface and the part yet liquid (solid-liquid interface) at the center, the temperature higher than it is in the solid or liquid due to temperature inversion. This means not only the dendrites tend to equally space away from each other but also grow further away from the interface deep into the liquid depending on the time they get to freeze. This results in the dendrites growing in a pattern of branch and leaf like structure so well, almost as if it was calculated before it was made. Well not almost... it was naturally calculated before it formed. It's thermodynamics in action. During freezing the latent heat of fusion given away by the freezing material is being exchanged at the solid-liquid interface which results in inversion of temperature in this region. The inversion simply denotes the raise in temperature above the freezing point as well as the ambient liquid temperature at the interface. Instead of the inversion of temperature slowing down the process, it instead gives the process a pattern. The material does not wait for this temperature to lower down as it finds a freezing opportunity on as a separate dendrite. Crystal starts forming and growing in shape of dendrites. Depending on what the localized thermodynamic conditions were, each flakes forms in different sizes and shapes, which is remarkably shown in the photography.

Tuesday, November 19, 2013

When we talk of going green, using solar, wind and other 'green' technologies, mostly we are unknowingly talking about energy harvesting. Harvesting energy from ambiance might be a solution that has been staring at us since a long time. We can totally eliminate the need for powering our electronics with external sources; batteries or fuel. There are a multitude of methods well within our capabilities.

Pakistan can take a great boost by starting with the small but numerous devices. The multitude of dry batteries that we import would not even be needed. A TV remote control can be powered by the same energy that we apply to press the 'button' if we use a piezoelectric material which converts the movement into enough voltage to send the signal. Powering handy devices with body heat, solar cells, piezoelectrics, or even use the excessive background noise that we have in form of radio waves and wifi signals on hundreds of channels to power devices.

On a macro-scale, The vast deserts are a good source of solar, wind and other forms of energy harvesting. Also, humans had always been having good living conditions prior to advent of electricity. Passive solar building design can take down the carbon foot print of a building to near zero.

It's time Pakistan takes steps towards such technologies. It might seem that highly developed nations develop such technologies and then it is transferred to us, but the truth is, most innovative and energy efficient technologies come from developing countries because they have to make do with the least possible resources. There is a huge range of technologies which were either developed for or by developing nations and later introduced to the developed ones.

As I explained in the last post about programmable materials, the processing of information is being decentralized to make it more viable... the power overload may not be any different from the information overload. The fact is, we do not need to reduce our energy consumption, we just need to reduce the wastage. Recycling and harvesting the wasted energy and making most devices self sufficient in regards to power is the obvious solution.